CN104821269B - Inductively Coupled Plasma Reactor - Google Patents

Abstract

There is provided a plasma reactor comprising: a vacuum chamber having a substrate support on which a treated substrate is positioned; a gas shower head supplying gas into the interior of the vacuum chamber; a dielectric window installed at an upper portion of the vacuum chamber; and a radio frequency antenna installed above the dielectric window. The gas shower head and the substrate support are capacitively coupled to plasma in the interior of the vacuum chamber and the radio frequency antenna is inductively coupled to the plasma in the interior of the vacuum chamber. The capacitive and inductive coupling of the plasma reactor allows generation of plasma in a large area inside the vacuum chamber more uniformly and more accurate control of plasma ion energy, thereby increasing the yield and the productivity. The plasma reactor includes a magnetic core installed above the dielectric window so that an entrance for a magnetic flux faces the interior of the vacuum chamber and covers the radio frequency antenna. Since the radio frequency antenna is covered by the magnetic core, the magnetic flux can be more strongly collected and the loss of the magnetic flux can be minimized.

Description

Inductively Coupled Plasma Reactor

This application is a divisional application of the patent application whose filing date is May 22, 2007, application number is 200710105100.0, and the invention title is "Inductively Coupled Plasma Reactor".

technical field

The present invention relates to a radio frequency (radio frequency) plasma source (plasma source), in particular to an inductively coupled plasma reactor capable of generating high-density plasma more uniformly.

Background technique

A plasma is a highly ionized gas containing equal numbers of positive ions and electrons. Plasma discharge is used for gas excitation to generate reactive gases including ions, radicals, atoms, molecules. Reactive gases are widely used in various fields, and are typically used in semiconductor manufacturing processes such as etching, deposition, cleaning, ashing, and the like.

There are various plasma sources for generating plasma, but typical examples thereof include capacitive coupled plasma and inductive coupled plasma using radio frequency.

Capacitively coupled plasma sources have the following advantages: correct capacitive coupling adjustment and high ion adjustment capability, and higher engineering productivity compared to other plasma sources. On the other hand, the energy of the RF power is connected to the plasma substantially exclusively via capacitive coupling, so that the plasma ion density increases or decreases only in response to increases or decreases in the capacitively coupled RF power. However, an increase in RF power increases ion impact energy. As a result, radio frequency power limitations are imposed in order to prevent damage due to ion impact.

On the other hand, the inductively coupled plasma source can easily increase the ion density by increasing the radio frequency power, and relatively reduce the resulting ion impact, which is suitable for obtaining high-density plasma. Therefore, inductively coupled plasma sources are generally used to obtain high-density plasmas. As a typical inductively coupled plasma source, a method using a radio frequency antenna (RF antenna) and a method using a transformer (referred to as transformer coupled plasma (transformer coupled plasma)) have been technically developed. Here, adding an electromagnet, a permanent magnet, or adding a capacitive coupling electrode improves the characteristics of the plasma, and technological development is carried out to improve reproducibility and controllability.

The radio frequency antenna generally uses a spiral type antenna or a cylinder type antenna. The radio frequency antenna is arranged outside the plasma reactor, and transmits the induced electromotive force to the inside of the plasma reactor through a dielectric window such as quartz. Inductively coupled plasma using a radio frequency antenna can easily obtain high-density plasma, but the uniformity of the plasma will be affected by the structural characteristics of the antenna. Therefore, it is necessary to improve the structure of the radio frequency antenna to obtain uniform high-density plasma.

However, in order to obtain a large-area plasma, it is necessary to enlarge the structure of the antenna and increase the power supplied to the antenna, which has limitations. For example, it is known that non-uniform plasma is generated on radiation lines by a standing wave effect. In addition, when high power is applied to the antenna, the capacitive coupling of the RF antenna increases, so that the dielectric window must be thickened, resulting in an increase in the distance between the RF antenna and the plasma, resulting in a problem that the effect of power transfer is reduced .

Recently, in the semiconductor manufacturing industry, with the miniaturization of semiconductor elements, the increase in the size of silicon wafer substrates used to manufacture semiconductor circuits, the increase in size of glass substrates used in the manufacture of liquid crystal displays, and the emergence of new substances to be processed For various reasons, it is required to further improve the plasma processing technology. In particular, a plasma source and a plasma processing technology having excellent processing capability for a large-area object to be processed are required.

Contents of the invention

The object of the present invention is to provide a plasma reactor, which uses all the advantages of inductively coupled plasma and capacitively coupled plasma, can improve the control ability of plasma ion energy, and produce more uniform large-area high-density plasma.

Another object of the present invention is to provide a plasma reactor, which can improve the magnetic beam transmission efficiency of the antenna, improve the control ability of plasma ion energy, and generate more uniform large-area high-density plasma.

Another object of the present invention is to provide a plasma reactor, which can improve the efficiency of magnetic beam transfer from the radio frequency antenna to the inside of the vacuum chamber, so that the supply of engineering gas is more uniform, thereby obtaining high-density uniform plasma.

A characteristic plasma reactor of the present invention for solving the above-mentioned technical problems includes: a vacuum chamber having a substrate support table carrying a substrate to be processed; a gas shower head supplying gas to the inside of the vacuum chamber; a dielectric window disposed on The upper part of the vacuum cavity; and the radio frequency antenna is arranged on the upper part of the dielectric window, wherein, the gas shower head and the substrate supporting platform are capacitively coupled with the plasma inside the vacuum cavity, and the radio frequency antenna is inductively coupled with the plasma inside the vacuum cavity.

The plasma reactor of another feature of the present invention for solving the above-mentioned technical problems includes a vacuum chamber, a dielectric window arranged on the upper part of the vacuum chamber, and a radio frequency antenna arranged on the upper part of the dielectric window, including a magnetic core, The magnetic beam entrance and exit of the magnetic core face the inside of the vacuum chamber, and the magnetic core is arranged on the upper part of the dielectric window along the radio frequency antenna to cover it.

The plasma reactor of the present invention generates plasma inside the vacuum chamber through capacitive and inductive coupling, thereby more uniformly generating large-area plasma, and at the same time, it is easy to correctly adjust the energy of plasma ions. In addition, the radio frequency antenna is covered by a magnetic core, which can transmit the magnetic flux inside the vacuum cavity more strongly, thereby suppressing the loss of the magnetic flux to the greatest extent.

According to the above-mentioned inductively coupled plasma reactor of the present invention, the gas shower head and the substrate supporting platform are capacitively coupled with the plasma inside the vacuum chamber, and the radio frequency antenna is inductively coupled with the plasma inside the vacuum chamber. In particular, the radio frequency antenna is covered by a magnetic core, which can concentrate a stronger magnetic flux and suppress the loss of the magnetic flux to the greatest extent. This kind of capacitive and inductive coupling makes it easy to generate plasma in the vacuum chamber, and it is easy to correctly adjust the energy of plasma ions. Therefore, yield and productivity can be improved in a semiconductor process. In addition, the gas shower head performs uniform gas injection on the upper part of the substrate support table, so that more uniform substrate processing can be performed.

Description of drawings

FIG. 1 is a sectional view of a plasma reactor according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an assembly structure of a radio frequency antenna and a gas shower provided on the upper portion of the plasma reactor in FIG. 1 .

Fig. 3 is a diagram showing an electrical connection structure of a radio frequency antenna and a shower head.

Fig. 4a is a diagram showing various examples of a modified electrical connection structure between a radio frequency antenna and a shower head.

Fig. 4b is a diagram showing various examples in which the electrical connection structure between the radio frequency antenna and the shower head is modified.

Fig. 4c is a diagram showing various examples in which the electrical connection structure between the radio frequency antenna and the shower head is modified.

Fig. 4d is a diagram showing various examples in which the electrical connection structure between the radio frequency antenna and the shower head is modified.

FIG. 5 is a diagram showing an example in which a dual power supply structure by power division is adopted.

FIG. 6 is a diagram showing an example of a dual power supply configuration using two power supply sources.

Fig. 7a is a diagram showing a power adjustment section formed between a radio frequency antenna and ground.

Fig. 7b is a diagram showing a power adjustment unit formed between the radio frequency antenna and the ground.

Fig. 8 is a sectional view of a plasma reactor according to a second embodiment of the present invention.

FIG. 9 is a diagram showing an arrangement structure of a radio frequency antenna and a gas shower provided above the plasma reactor in FIG. 8 .

FIG. 10 is a diagram showing an example in which a columnar radio frequency antenna is also provided on the outer side wall portion of the vacuum chamber.

Fig. 11 is a cross-sectional view of a plasma reactor according to a third embodiment of the present invention.

FIG. 12 is a diagram showing an arrangement structure of a radio frequency antenna and a gas shower provided above the plasma reactor in FIG. 11 .

Fig. 13 is a diagram visually representing a magnetic flux induced inside a vacuum chamber by a radio frequency antenna and a magnetic core through a dielectric window.

FIG. 14 is a diagram showing an example in which a dual power supply structure by power division is adopted.

FIG. 15 is a diagram showing an example of a dual power supply structure using two power supply sources.

FIG. 16 is a cross-sectional view showing an example plasma reactor using a plate-type magnetic core.

Fig. 17 is an exploded perspective view of a plate-type magnetic core, a radio frequency antenna and a nozzle.

Fig. 18 is a sectional view of a plasma reactor according to a fourth embodiment of the present invention.

FIG. 19 is a diagram showing the arrangement structure of a radio frequency antenna and a gas shower head provided on the upper portion of the plasma reactor in FIG. 18 .

Fig. 20 is a cross-sectional view showing an example plasma reactor using a plate-type magnetic core.

FIG. 21 is a diagram showing an example in which a columnar radio frequency antenna and a magnetic core are also provided on the outer side wall portion of the vacuum chamber.

Fig. 22 is a sectional view showing a plasma reactor according to a fifth embodiment of the present invention.

Fig. 23a is a diagram showing an example of a shape of a radio frequency antenna configured in a spiral shape.

Fig. 23b is a diagram showing an example of the shape of the radio frequency antenna configured in concentric circles.

Fig. 24a is a diagram showing an electrical connection structure of a radio frequency antenna.

Fig. 24b is a diagram showing the electrical connection structure of the radio frequency antenna.

FIG. 25 is a diagram showing an example in which a dual power supply structure by power division is adopted.

FIG. 26 is a diagram showing an example of a dual power supply structure using two power supply sources.

Fig. 27 is a partial cross-sectional view showing a modification in which a gas supply channel is formed through the central portion of the magnetic core.

detailed description

Hereinafter, the plasma reactor of the present invention will be described in detail by explaining preferred embodiments of the present invention with reference to the accompanying drawings. The embodiments of the present invention can be modified in various ways, and the scope of the present invention is not limited to the following embodiments. This embodiment is provided to describe the present invention more completely for those skilled in the art. Therefore, for clearer description, the shapes of components and the like in the drawings are exaggerated. In order to facilitate understanding of the drawings, the same reference numerals are assigned to the same components as much as possible. In addition, detailed technical descriptions are omitted for known functions and structures that are judged to obscure the gist of the present invention.

FIG. 1 is a sectional view of a plasma reactor according to a first embodiment of the present invention.

Referring to FIG. 1 , the plasma reactor includes a vacuum chamber 100 composed of a lower body 110 and an upper cover 120 . Inside the vacuum chamber 100, a substrate support table 111 on which a substrate to be processed 112 is mounted is provided. A gas outlet 113 for exhaust gas is provided on the lower body 110 , and the gas outlet 113 is connected to a vacuum pump 115 . The substrate to be processed 112 is, for example, a silicon wafer substrate used for manufacturing a semiconductor device, or a glass substrate used for manufacturing a liquid crystal display or a plasma display.

The lower body 110 is made of metal materials such as aluminum, stainless steel, and copper. Or made of coated metal, such as bipolar treated aluminum, nickel-plated aluminum. Or made of refractory metal (refractory metal). In addition, as an alternative, the lower main body 110 may be entirely made of electrically insulating materials such as quartz and ceramics, or may be made of other materials suitable for plasma treatment. The upper cover 120 and the lower body 110 can be made of the same material or different materials.

A dielectric window 130 with an open center is provided on the inner upper portion of the vacuum chamber 100 . A gas shower head 140 is provided on the opening of the dielectric window 130 . The gas shower head 140 includes at least one gas distribution plate 145 made of conductive material. A silicon plate 146 formed with a plurality of gas injection holes is provided on a portion of the gas shower head 140 in contact with the inner region of the vacuum chamber 100 . A gas inlet 121 connected to the gas shower head 140 is provided at the center of the upper cover 120 . A radio frequency antenna 151 is disposed in the upper space 123 between the upper cover 120 and the dielectric window 130 .

The dielectric wall 132 is selectively disposed along the inner wall of the vacuum chamber 100 . It is preferable to have a structure in which the dielectric wall 132 and the dielectric window 130 are integrally formed. However, they can also be formed as separate structures. The dielectric wall 132 is disposed on a portion slightly lower than the substrate supporting body 111 as a whole, so as to prevent the lower body 110 from being damaged or polluted during the process. The dielectric window 130 and the dielectric wall 132 are made of insulating materials such as quartz or ceramics, for example.

The dielectric window 130 has a structure passing between the upper cover body 120 and the lower body 110, but at this time, O-rings 114, 122 are respectively provided on the joint surfaces for vacuum insulation. In addition, O-rings 125 and 124 for vacuum insulation are also respectively provided on the joint surface of the dielectric window 130 and the shower head 140 and the joint surface of the shower head 140 and the upper cover 120 .

FIG. 2 is a diagram showing an assembly structure of a radio frequency antenna and a gas shower provided on the upper portion of the plasma reactor in FIG. 1 .

Referring to FIG. 2 , the radio frequency antenna 151 is arranged in a flat spiral structure with the gas shower head 140 as the center. A faraday shield is provided between the dielectric window 130 and the radio frequency antenna 151 . The Faraday shield 142 is an optional structure and may or may not be provided. The Faraday shield 142 may or may not have a structure electrically connected to the gas shower head 140 .

In addition, referring to FIG. 1 , one end of the radio frequency antenna 151 is electrically connected to the first power supply source 160 for supplying radio frequency via an impedance matcher 161 , and the other end is grounded. The radio frequency antenna 151 is inductively coupled with the internal plasma of the vacuum chamber. The substrate support 111 is electrically connected to the second power supply source 162 for supplying radio frequency via an impedance matching device 163 , and the gas shower head 140 is grounded. The gas shower head 140 and the substrate support 111 constitute a pair of capacitive electrodes, which are capacitively coupled with the plasma inside the vacuum chamber 100 . The first and second power supply sources 160 and 162 can be formed by using a radio frequency power supply source capable of controlling the output voltage without a special impedance matching device. The phase relationship between the radio frequency signal for capacitive coupling and the radio frequency signal for inductive coupling has an appropriate relationship, for example, a phase relationship of about 180 degrees.

In the plasma reactor according to the first embodiment of the present invention, the gas shower head 140 and the substrate supporting platform 111 are capacitively coupled to the plasma inside the vacuum chamber 100 , and the radio frequency antenna 151 is inductively coupled to the plasma inside the vacuum chamber 100 . Generally, in an inductively coupled plasma source using a radio frequency antenna, the density and uniformity of plasma are affected by the shape of the radio frequency antenna. From this point of view, the plasma reactor of the present invention has a capacitively coupled gas shower head 140 at the central part, and has a radio frequency antenna 151 configured as a flat plate helix at its periphery, thereby obtaining a more uniform gas flow inside the vacuum chamber. plasma.

Such capacitive and inductive coupling facilitates plasma generation and correct regulation of plasma ion energy within vacuum chamber 100 . Therefore, engineering productivity can be maximized. In addition, the gas shower head 140 is located on the upper part of the substrate support table 111 , so that uniform gas injection can be performed on the upper part of the substrate 112 to be processed, and more uniform substrate processing can be performed.

Fig. 3 is a diagram showing an electrical connection structure of a radio frequency antenna and a shower head.

Referring to FIG. 3 , it can be modified that the radio frequency antenna 151 and the gas shower head 140 are electrically connected in series. That is, one end of the radio frequency antenna 151 is connected to the first power supply source 160 through the impedance matching device 161 , and the other end is connected to the gas shower head 140 . Also, the gas shower head 140 is grounded. The electrical connection relationship between the gas shower head 140 and the radio frequency antenna 151 can be modified and implemented as follows.

4a to 4d are diagrams showing various examples in which the electrical connection structure of the radio frequency antenna and the shower head is modified.

(a) in FIG. 4a to FIG. 4d shows the physical configuration structure and electrical connection relationship of the radio frequency antenna 151 and the gas shower head 140, and (b) expresses them with electrical symbols and illustrates their connection relationship.

The gas shower head 140 and the radio frequency antenna 151 shown in FIG. 4 a are connected in the same manner as that illustrated in FIG. 4 . One end of the radio frequency antenna 151 is electrically connected to the first power supply source 160 through an impedance matching device 161 , and the other end is electrically connected to the gas shower head 140 . Gas showerhead 140 is grounded.

The gas shower head 140 and the radio frequency antenna 151 shown in FIG. 4 b are connected in such a way that the gas shower head 140 is first electrically connected to the first power supply source 160 , and then the radio frequency antenna 151 is connected to the gas shower head 140 and grounded.

The gas shower head 140 and the radio frequency antenna 151 shown in Fig. 4c and Fig. 4d are connected in such a way that the radio frequency antenna 151 is formed by two separate antennas 151a and 151b, and the gas shower head 140 is electrically connected therebetween. Among them, the radio frequency antenna 151 in FIG. 4c has two separated antennas 151a and 151b wound in the same winding direction, and has a configuration structure located on the outer contour and a configuration structure located on the inner contour.

In addition, in the radio frequency antenna 151 shown in FIG. 4d, two separate antennas 151a, 151b are wound side by side around the gas shower head 140 in a flat spiral shape. In addition, an outer end of one antenna 151 a located on the outer shell is connected to the first power supply source 160 via an impedance matching device 161 , and the other end is connected to the gas shower head 140 . The inner end of another antenna 151b located in the inner profile is connected to the gas shower head 140, and the outer end is grounded.

The electrical connection modes of the gas shower head 140 and the radio frequency antenna 161 illustrated in FIGS. 4 a to 4 d above have various electrical connection modes besides the above examples. This type of electrical connection can also be similarly applied to examples described later. In addition, as for the power supply method of the radio frequency antenna 161 and the substrate support table 111, various supply methods can be adopted as described below. In addition, the number of power supply sources for supplying the radio frequency antenna can also be variously modified.

FIG. 5 is a diagram showing an example in which a dual power supply structure by power division is adopted.

Referring to FIG. 5 , the following power division supply structure is adopted: the radio frequency supplied from the first power supply source 160 is distributed via the power distribution unit 164 , and is divided and supplied to the radio frequency antenna 151 and the substrate support table 111 . The power distribution unit 164 can perform power division in various ways, such as power division using a transformer, power division using a plurality of resistors, power division using capacitors, and the like. The substrate support table 111 is supplied with radio frequency divided from the first power supply source 160 and a radio frequency supplied from the second power supply source 162 . At this time, the first and second power supply sources 160 and 162 provide radio frequencies with different frequencies.

FIG. 6 is a diagram showing an example of a dual power supply configuration using two power supply sources.

Referring to FIG. 6, the substrate support table 111 is supplied with two radio frequencies via two power supply sources 162a, 162b providing frequencies different from each other.

Therefore, when the substrate supporting table 111 is supplied with radio frequencies of different frequencies, various power supply structures such as a power division structure or a structure using an independent power supply can be adopted. The dual power supply structure of the substrate support table 111 can generate plasma more easily inside the vacuum chamber 100 , further improve plasma ion energy regulation on the surface of the processed substrate 112 , and further improve engineering productivity.

The single or dual power supply structure of the substrate support table 111 can realize various electrical connection modes by mixing the various electrical connection modes of the RF antenna 151 and the gas shower head 140 described above in FIGS. 5 a to 5 d.

7a and 7b are diagrams showing a power adjustment unit formed between a radio frequency antenna and a ground.

7a and 7b, a power regulator 170 is formed between the radio frequency antenna 151 and the ground. The power adjustment unit 170 is constituted by, for example, a variable capacitor 171a or a variable inductor 171b. The inductive coupling energy of the radio frequency antenna 151 can be adjusted through variable capacitance control of the power adjustment unit 170 . Such a power adjustment unit 170 may be formed between the gas shower head 140 and the ground in order to adjust capacitive coupling energy.

The configuration of the power adjustment unit 170 can mix the various power supply structures described above with various electrical connection modes of the gas shower head 140 and the radio frequency antenna 161 to realize more various electrical connection modes. This electrical connection method can also be applied to the examples described later.

Fig. 8 is a sectional view of a plasma reactor according to a second embodiment of the present invention. FIG. 9 is a diagram showing an arrangement structure of a radio frequency antenna and a gas shower provided above the plasma reactor in FIG. 8 .

Referring to FIG. 8 and FIG. 9, the plasma reactor of the second embodiment of the present invention has basically the same structure as that of the above-mentioned first embodiment. Therefore, overlapping descriptions of the same configurations are omitted. The structure of the vacuum chamber 100a in the plasma reactor of the second embodiment is slightly different from the vacuum chamber 100 in the above-mentioned first embodiment. The vacuum chamber 100a of the plasma reactor of the second embodiment has a structure in which the dielectric window 130 formed on the upper portion of the lower main body 110 also serves as an upper cover. On the upper part of the dielectric window 130, there is a cover member 126 which covers the radio frequency antenna 151 as a whole. The cover member 126 is composed of a conductive or non-conductive substance. The shower head 140 has a structure that protrudes toward the substrate supporting table 111 lower than the dielectric window 130 .

FIG. 10 is a diagram showing an example in which a columnar radio frequency antenna is also provided on the outer side wall portion of the vacuum chamber.

Referring to FIG. 10 , the radio frequency antenna 151 has a planar helical structure and is disposed on the upper portion of the dielectric window 130 , and is disposed on the outer side wall of the vacuum chamber 100 as an expanded structure in a cylindrical structure. The structure of the dielectric window 130 has a matching structure thereto. In addition, the cover part also has an expanded structure to cover the RF antenna 151 disposed on the side wall.

Fig. 11 is a cross-sectional view of a plasma reactor according to a third embodiment of the present invention.

Referring to FIG. 11, the plasma reactor of the third embodiment has basically the same structure as that of the first embodiment described above. Therefore, overlapping descriptions of the same configuration are omitted. In particular, in the plasma reactor of the third embodiment, the radio frequency antenna 151 is covered by the magnetic core 150, which can concentrate the magnetic flux more strongly and can suppress the loss of the magnetic flux to the greatest extent.

Fig. 12 is a diagram showing the arrangement structure of the radio frequency antenna and the gas shower head arranged on the upper part of the plasma reactor of Fig. 11, and Fig. 13 is a visual representation of the magnetic field induced by the radio frequency antenna and the magnetic core through the dielectric window inside the vacuum chamber diagram.

Referring to FIG. 12 , the radio frequency antenna 151 is arranged in a flat spiral structure with the gas shower head 140 as the center, and the radio frequency antenna 151 is covered by the magnetic core 150 . The vertical cross-sectional structure of the magnetic core 150 has a shoe shape, and the magnetic flux entrance 152 of the magnetic core 150 faces the dielectric window 130 and covers it along the radio frequency antenna 151 . Therefore, as shown in FIG. 13 , the magnetic flux generated by the radio frequency antenna 151 is concentrated by the magnetic core 150 and induced inside the vacuum chamber 100 via the dielectric window 130 . The magnetic core 150 can be made of ferrite or other alternative materials. The magnetic core 150 may be constructed by assembling a plurality of shoe-shoe-shaped ferrite chips. In addition, all ferrite cores having a shoe-shaped vertical cross-sectional shape or a structure wound into a flat plate spiral can be produced and used.

In the plasma reactor according to the third embodiment of the present invention, the gas shower head 140 and the substrate supporting platform 111 are capacitively coupled to the plasma inside the vacuum chamber 100, and the radio frequency antenna 151 is inductively coupled to the plasma inside the vacuum chamber 100. . In general, for an inductively coupled plasma source using a radio frequency antenna, the density and uniformity of the plasma will be affected depending on the shape of the radio frequency antenna. From this point of view, the plasma reactor of the present invention is equipped with a capacitively coupled gas shower head 140 in the central part, and has a radio frequency antenna 151 configured as a flat-plate helix at its periphery, so that a more uniform plasma can be obtained inside the vacuum chamber. . In particular, the radio frequency antenna 151 is covered by the magnetic core 150, which can concentrate a stronger magnetic flux, thereby suppressing the loss of the magnetic flux to the greatest extent.

FIG. 14 is a diagram showing an example of a dual power supply configuration using power division, and FIG. 15 is a diagram showing an example of a dual power supply configuration using two power supply sources.

The plasma reactor illustrated in FIGS. 14 and 15 has basically the same structure as the plasma reactor shown in FIGS. 5 and 6 described above. In particular, in the plasma reactor shown in FIG. 14 and FIG. 15 , each radio frequency antenna 151 is covered by a magnetic core 150 , which can concentrate the magnetic flux more strongly, thereby suppressing the loss of the magnetic flux to the greatest extent.

FIG. 16 is a cross-sectional view showing an exemplary plasma reactor using a plate-shaped magnetic core, and FIG. 17 is an exploded perspective view of a plate-shaped magnetic core, a radio frequency antenna, and a shower head.

Referring to FIG. 16 and FIG. 17 , as an alternative, a plate core 190 may be used to cover the RF antenna 151 . The plate-type magnetic core 190 has an opening 191 corresponding to the dielectric window 130 , and has a plate-shaped main body 192 entirely covering the upper portion of the dielectric window 130 . An antenna installation groove 193 is formed on the bottom surface of the flat-shaped main body 192 along the area where the radio frequency antenna 151 is located. The radio frequency antenna 151 is arranged along the antenna installation slot 193 , and the whole is covered by the plate core 190 . Such a plate-shaped magnetic core 190 can be used as an alternative to the above-mentioned shoe-shaped magnetic core 150 .

18 is a cross-sectional view showing a plasma reactor according to a fourth embodiment of the present invention, and FIG. 19 is a diagram showing an arrangement structure of a radio frequency antenna and a gas shower provided above the plasma reactor in FIG. 18 .

Referring to Fig. 18 and Fig. 19, the plasma reactor according to the fourth embodiment of the present invention has basically the same structure as that of the above-mentioned third embodiment. Therefore, overlapping descriptions of the same configurations are omitted. However, the structure of the vacuum chamber 100a in the plasma reactor of the fourth embodiment is slightly different from the vacuum chamber 100 of the third embodiment described above. The vacuum chamber 100a of the plasma reactor of the fourth embodiment has a structure in which the dielectric window 130 formed on the upper portion of the lower main body 110 also serves as an upper cover. On the upper part of the dielectric window 130, there is a cover member 126 that covers the radio frequency antenna 151 and the magnetic core 150 as a whole. The cover member 126 is composed of a conductive or non-conductive substance. The shower head 140 has a structure protruding lower toward the substrate support table 111 than the dielectric window 130 .

Fig. 20 is a cross-sectional view showing an example of a plasma reactor using a plate-type magnetic core.

Referring to FIG. 20 , as described in the above-mentioned third embodiment, the radio frequency antenna 151 may be covered with a plate-type magnetic core 190 .

Fig. 21 is a diagram showing an example in which a columnar radio frequency antenna and a magnetic core are also provided on the outer side wall of the vacuum chamber.

Referring to FIG. 21 , the radio frequency antenna 151 has a planar helical structure, is disposed on the upper portion of the dielectric window 130 , and is disposed on the outer side wall portion of the vacuum chamber 100 in a cylindrical structure as an expanded structure. As a structure of the dielectric window 130, it is made to have a structure matching the above-mentioned structure, and the magnetic core 150 is provided likewise. In addition, the cover part also has an expanded structure to cover the radio frequency antenna 151 and the magnetic core 150 disposed on the side wall.

Fig. 22 is a sectional view of a plasma reactor according to a fifth embodiment of the present invention.

Referring to FIG. 22, an inductively coupled plasma reactor has a vacuum chamber 100 composed of a lower body 110 and a dielectric window 120 constituting the top of the lower body. Inside the vacuum chamber 100, a substrate support table 111 on which a substrate to be processed 112 is mounted is provided. A gas outlet 113 for exhaust gas is provided on the lower body 110 , and the gas outlet 113 is connected to a vacuum pump 115 .

A gas shower head 140 is provided on the inner upper portion of the vacuum chamber 100 . The gas shower head 140 includes at least one gas distribution plate 141 made of conductive material. A silicon plate 146 formed with a plurality of gas injection holes is provided on a portion where the gas shower head 140 is in contact with the inner region of the vacuum chamber 100 .

The dielectric window 120 is provided with a gas injection tube 122 connected to the gas shower head 140 , and the end 121 of the gas injection tube 122 is connected to the gas shower head 140 . For vacuum insulation, O-rings 123 are respectively provided between the dielectric window 130 and the lower body 110 . A radio frequency antenna 151 is disposed close to the upper portion of the dielectric window 120 , and a magnetic core 150 that covers the radio frequency antenna 151 as a whole is disposed.

One end of the radio frequency antenna 151 is electrically connected to the first power supply source 160 for supplying radio frequency via an impedance matcher 161 , and the other end is grounded. The radio frequency antenna 151 is inductively coupled with the plasma inside the vacuum chamber. The substrate supporting table 111 is electrically connected to the second power supply source 162 for supplying radio frequency through the impedance matching device 163 , and the gas shower head 140 is grounded. The gas shower head 140 and the substrate supporting table 111 form a pair of capacitive electrodes, and are capacitively coupled with the plasma inside the vacuum chamber 100 . The first and second power supply sources 160 and 162 can be configured by using radio frequency power supply sources capable of controlling the output voltage without requiring a dedicated impedance matching device. The phase relationship between the radio frequency signal for capacitive coupling and the radio frequency signal for inductive coupling has an appropriate relationship, for example, a phase relationship of about 180 degrees.

Fig. 23a and Fig. 23b are diagrams showing examples in which the shape of the radio frequency antenna is formed into a flat helical shape or a concentric circle shape.

Referring to Fig. 23a and Fig. 23b, the radio frequency antenna 151 is composed of more than one radio frequency antenna having a flat spiral structure or a concentric circular structure. Multiple radio frequency antennas 151 are overlapped in more than two layers. The magnetic core 150 has a planar body that covers the RF antenna 151 as a whole, and the antenna installation groove 152 is arranged in a spiral or concentric circle along the area where the RF antenna 151 is located.

24a and 24b are diagrams showing the electrical connection structure of the radio frequency antenna.

24a and 24b, the radio frequency antenna 151 is composed of multiple antenna units 151a, 151b, 151c, and the multiple antenna units 151a, 151b, 151c have a series or parallel electrical connection structure. Or have a series and parallel electrical connection structure.

In the inductively coupled plasma reactor of the present invention, the gas shower head 140 and the substrate supporting platform 111 are capacitively coupled to the plasma inside the vacuum chamber 100 , and the radio frequency antenna 151 is inductively coupled to the plasma inside the vacuum chamber 100 . In particular, the radio frequency antenna 151 is covered by the magnetic core 150, which can concentrate a stronger magnetic flux, thereby suppressing the loss of the magnetic flux to the greatest extent. In this way, the capacitive and inductive coupling makes it easy to generate plasma in the vacuum chamber 100 and to easily adjust the energy of plasma ions correctly. Therefore, engineering productivity can be maximized. In addition, the gas shower head 140 is located on the upper part of the substrate support table 111, so that uniform gas injection can be performed on the upper part of the substrate 112 to be processed, and more uniform substrate processing can be performed.

FIG. 25 is a diagram showing an example in which a dual power supply structure by power division is adopted.

Referring to FIG. 25 , the following power division and supply structure is adopted: the radio frequency supplied from the first power supply source 160 is distributed via the power distribution unit 164 , and is divided and supplied to the radio frequency antenna 151 and the substrate support table 111 . The power distribution unit 164 can perform power division in various ways, such as power division using a transformer, power division using a plurality of resistors, power division using capacitors, and the like. The substrate support table 111 is supplied with radio frequency divided from the first power supply source 160 and a radio frequency supplied from the second power supply source 162 . At this time, the first and second power supply sources 160 and 162 provide radio frequencies with different frequencies from each other.

FIG. 26 is a diagram showing a dual power supply structure using two power supply sources.

Referring to FIG. 26, the substrate support table 111 is supplied with two radio frequencies via two power supply sources 162a, 162b providing frequencies different from each other.

Therefore, when the substrate supporting table 111 is supplied with radio frequencies of different frequencies, various power supply structures such as a power division structure or a structure using an independent power supply can be adopted. The dual power supply structure of the substrate support table 111 can generate plasma more easily inside the vacuum chamber 100 , further improve plasma ion energy regulation on the surface of the processed substrate 112 , and further improve engineering productivity.

The single or dual power supply structure of the substrate support table 111 can realize more various electrical connection modes by mixing the various electrical connection modes of the RF antenna 151 and the gas shower head 140 described in FIGS. 4a to 4d.

Fig. 27 is a partial cross-sectional view showing a modification in which a gas supply channel is formed through the central portion of the magnetic core.

Referring to FIG. 27, the gas supply structure may be modified as follows: an opening 153 is formed at the center of the magnetic core 150, and a corresponding opening 124 is formed at the center of the dielectric window 120 for gas supply.

The plasma reactor of the present invention can be modified in many ways and can be adopted in various ways. However, the present invention is not limited to the above specific embodiments, and includes all modifications, equivalents and substitutes within the gist and scope of the present invention defined by the claims.

Claims (9)

1. A plasma reactor, wherein, Including: a vacuum chamber with a substrate support table carrying a substrate to be processed; a dielectric window disposed on the upper part of the vacuum chamber; A gas shower head is arranged inside the vacuum chamber and on the upper part of the substrate support table; a radio frequency antenna, which is arranged on the upper part of the dielectric window, and is wound around the gas shower head, and arranged in a helical structure or a concentric circular structure; and A magnetic core, which is assembled from multiple shoe-shoe-shaped ferrite chips to cover the radio frequency antenna, The first power supply source distributes and divides the radio frequency provided by the power distribution unit to the radio frequency antenna and the substrate support table; The second power supply source supplies a radio frequency different from that of the first power supply source to the substrate support table. 2. The plasma reactor according to claim 1, characterized in that, One end of the radio frequency antenna is connected to the ground, or the gas shower head is connected to the ground in one of the connection methods. 3. The plasma reactor according to claim 1, characterized in that, The radio frequency antenna has a multi-layered structure. 4. The plasma reactor according to claim 1, characterized in that, comprising: The gas showerhead includes one or more gas distribution plates. 5. The plasma reactor according to claim 1, characterized in that, A Faraday shield disposed between the radio frequency antenna and the dielectric window is included. 6. The plasma reactor according to claim 1, characterized in that, The gas shower head and the substrate supporting platform are capacitively coupled with the plasma inside the vacuum chamber, and the radio frequency antenna is inductively coupled with the plasma inside the vacuum chamber. 7. The plasma reactor according to claim 1, characterized in that, The dielectric window, radio frequency antenna and magnetic core are arranged inside the vacuum chamber, and include an upper cover covering the upper part of the vacuum chamber. 8. The plasma reactor according to claim 1, characterized in that, A dielectric wall is included along an inner wall of the vacuum chamber. 9. The plasma reactor according to claim 1, characterized in that, The face of the gas shower head that interfaces with the interior region of the vacuum chamber includes a silicon flat plate.